* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: Helvetica Neue, Helvetica, PingFang SC, Hiragino Sans GB, Microsoft YaHei, SimSun, sans-serif;
  font-weight: 300;
}
ul,
li {
  list-style: none;
  padding: 0;
}

html{
  font-size: 16px;
}

@media screen and (max-width:900px) {
  html{
    font-size: 12px;
  }
}
